Clamp for scaffolding



June 16, 1936. I D. H. JONES 7 2,044,700,

Patented June 16, 1936 cLAMP FOR SCAFFOLDING David Henry JoneS London, England, assignor of one-half to Scaffolding (Great Britain) Limited, London, England Application September 26, 1935, Serial No. 42,361 In Great'Britain December 2'7, 1934 q 6 Claims. (01. sc -4.0)

This-invention relates toa clamp for scaffoldingand has for its object the provision of a clamp ior clamping two scaffolding members arranged at an angle relatively to each otherwhich clamp can be applied without threading the clamp on either of the scaffolding members. i

This invention has special reference to clamping a putlog in position on a horizontal tubular member of a scaiiolding erection but the invention is not limited to this application. In such a clamp it is necessary to apply the clamp with- V out threading the clamp either on to the putlog or on to thetube, but unlike the couplers which are employed for coupling two tubes "in relation to each other when both ofsuch tubes liein the quired to grip the putlog to the tube so as to 30 base of the U embracesthe tube. The sides foriningthe U'are recessed laterallyfso as to form two correspondinghooks'which can be ap plied laterally to one ofthe scaifolding members and thus avoid threadingsmthat, for instance,

afterthe clamphas beenapplied=below the tubular member by sliding the clamp longitudinally of the tube towards the putlog, the latter is received within the hooks, and on the clamp being tightened by the introduction of a distancing device in the trough of the 'U to: bear between the said trough and the underside of the tube,

the putlog and the tube are firmly clampedtoi Fig. 1 isa perspective onal' scaffo1din'g' tube.

gether and are held securelyagainst slipping relatively to each other. a

"Clamps according'to this invention are illustrated" in 'the accompanying" drawings, in Which: 3 y 1 view of one form of the clamping member. I 7 Figs.'2 and 3 aretwo 'views takenat right angles to each other illustrating the application-of the clamping member shown in to a putlog and a scafiolding' tube.

Figs. land 5 are two'v'iews taken'at rightangles to each other of another form of clamping member-shown'appliedto an upright and a diag- Figs. 6 and '7 are similar views to'Figs'. 2*and3 butillustrate 'tIie'appIication of a chair to the clamping member.

Fig. 8 is a section on the line 8--8 in Fig. 6. The clamping member isconstructed of a single piece of sheet metal a cut out at a to provide lateral recesses in one side which forms two corresponding hook shaped ends a a After being cutto the required shape the metal is bent'to a U-shape forming a semi-cylindrical central'part ar -between the two hooks a a which central part'is rounded to receive a scaffoldingtube.- This central part is formed with a boss (1. either integral with the central part or separate and fixed thereto. This boss is internally tapped to receive a clamping screw b. This screw b is positioned with respect to the hook members so as to transmit a direct thrust through the inserted scafiolding'members against the opposite side of the clamping device, thus securely locking all the parts in assembled relation. 1 I

In the application of the clamping member the hook shaped ends are first'passed upwardly one ateither side of the scafiolding tube until its central part' w embraces said tube." Now, from this position, by-slidingthe clamping memleer along longitudinally of the tube c, the horizontal putlog d can be receivedwithin the two hook shaped ends a a When in this position, by' turning -the clamping screw, the clamp is forced downwardly until the hook-shaped ends press the putlog 0. against the tube 0 and thus firmly clampl them together and hold them" against slipping relatively to each other. 01? course, the clamp could, if desired, be fixed in the reverse-position with thebase ofthe -U on top of the upper tube and the hooks under the lower tube. i As shown, the cut-away part forming the hook-shaped ends is preferably not of circular form but is arcuate at the top and is rectangular at the bottom so that it can be used for square or rectangular shaped putlogs in addition to round putlogs. v v

Such a clamp enables a toe board e to beaccommodated' between the two hook-shaped ends and also acts as a stop for the scaffold boards) supported on the putlog.

For application'to scaffolding tubes 0 :1 arranged. as shown in Figs. 4' and at an angle other" than a right angle to each other, the clamping member would be constructed with the hook portions a a off set from each other.

In the preferred arrangement shown in Figs. 6 to 8 the clamp is provided with a chair fitting g arrangedto fit between the two tubes" when the clamp is'clamped in position, and by. the use of such a chair fitting it is found that the frictional resistance to load pressure between the tubes is increased to a very substantial extent. Thechair fitting conveniently comprises a metal tongue 9 extending'at right angles tothehooks and formed on its upper and lower surfaces with recesses g g shaped to accommodate the tubes 0 and d which are to be united by the clamps. The tongue is connected to the clamp in such a way as to give it the small degree of freedom of movement necessary to prevent the tongue from obstructing the clamp during the placing of the latter in position on the tubes. conveniently be formed with an extended arm g slidable in a slot g in the hook portion a and having its end 9 shaped to fit in counter-sunk relationship in an outwardly bent portion a on the books. The end g ofthe tongue arm g is made detachable and is fixed by a screw 9 so that after the arm has been inserted through the slot g the end may be attached to the arm which will then prevent its detachment from the clamp but will permit the chair to be slid endwise in order to allow the clamp to be applied to the scaifolding member in the manner hereinbefore described, and when the clamp is in position but before the clampingscrew has been tightened the chair will he slid into the illustrated position so as to come in between the two tubes. 7

It will be understood that a chair as shown in Figs. 6, 7 and 8 may be applied to the Figs. 4 and 5 construction, provided that the recesses g and g arelocated at the required angle corresponding to that of the tubes relatively to each other.

What I claim as my invention and desire to secure by Letters Patent is:--

1. A clamp for clamping two scaffolding members together comprising a plate metal clamping member of U-shape having a central portion adapted to embrace'one scaffolding member and two ends with their flat sides parallel to each other, said ends having lateral recesses in their edges on one side to form two hook portions,-and said ends being off-set laterally relatively to each other adapted to be applied laterally to the other scaffolding member which is inclined obliquely to the scaffolding member embraced by the clamping'member and which is received in said hook portions and a clamping'device on part of said clamping member for pressing the scaffolding membersagainst eachother and against'another part of the clamping member to clamp them together.

v 2. A clamp for clamping two scaffolding members together ;comprising a single plate metal clamping member of U-shape having a central portion adapted to embrace onescaifolding member and two ends,-said ends having lateral-recesses in their edges onone side to-form two-corresponding hook portions adapted to be applied laterally to the other scaifolding member, a chair movably mounted on said clamping member so that it can be moved into a position in which itpermits the clamping member'to be applied to the scaffolding members without threading and when applied the chair can be moved into-alposition between said scaifolding 'members and a clampingdevice on one end of said clamping member for applying pressure between the scaffolding members, the chair and the-clamping member to clamp them together.

3. -A'clamp for clamping'twoscaifolding members together, comprising a single plate metal clamping member'of -U-shape having a central portion adapted to embrace one scaffolding member andtwo ends, 'saidends having lateral recesses in their edges on one'sideto form two corresponding hook portions whereby the clamping member is adapted to be-applied laterally to the other scaffolding member and having a slot in one To this end the tongue may v of said hook portions, a chair formed with an extended arm slidably mounted in said slot adapted to permit the chair to be slid either into a position clear of the space between the two hook portions or into a position in between the said scaffolding members and a clamping device on one end of said clamping member for pressing the scaffolding members against each other and against another part of the clamping member to clamp them together. I

4. A clamp for clamping two scaffolding members together comprising a single U-shaped clamping member adapted to embrace one scaffolding member, said clamping member having the edges on one side recessed laterally to form two hook portions adapted to receive the other scaffolding member and having a slot in one of said hook portions, a chair formed with an extended arm slidably mounted in said slot adapted to permit the chair to be slid either into a position clear of the space between the two hook portions or into a position in between the said scaffolding members, a detachable end on said arm adapted when removed to permit the chair to be detached but when attached prevents the chair from sliding completely off the clamping member and a distancing device in the base of said clamping member for applying pressure between the scaffolding members and the clamping member to clamp them together.

5. A clamp for clamping two scaffolding members together comprising a single U-shaped clamping member adapted to embrace one scaffolding member, said clamping member having the edges on one side recessed laterally to form two hook portions adapted to receive the other scaffolding member and having a slot in one of said hook portions and a counter-sunk recess surrounding said slot on the interior of the clamping member, a chair formed with an extended arm slidably'mounted in said slot adapted to permit the 'chair to be slid laterally from a position clear of the space between the two hook portions into a position in between said hook portions in which it is adapted to engage between the scaffolding members, a detachable end on said arm adapted to engage in said counter-sunk recess when the chair-is clear of the space between the two hook portions said detachableend when removed permitting the chair to be detached but when attached prevents the chair from sliding completely off the clamping member and a distancing device in the base of said clamping member forapplying pressure between the scaffolding members and the clamping member-to clamp them together.

6. A clamp for clamping two scaffolding members together comprising, in combination, a U- shapedmetal plate with its central part providing a semi-cylindrical portion adapted to embrace one scaffolding member and its two arms having their fiat sides parallel to each other, said-armshaving lateral recesses in corresponding side edges whereby said -U-shaped plate'can be applied laterally to the other scaffolding member and a clamping device attached at one endof said U- shaped plate, the whole forming a unit, said clamping device being positioned to press the scaffolding members against each other and simultaneously toward and against theopposite-endof the said plate. I

DAVID HENRYJONES. 

